1. Field of the Disclosure
The present disclosure relates to high-voltage switches implemented in CMOS (Complementary Metal-Oxide-Semiconductor) processes.
2. Description of the Related Art
Memory devices are electronic devices arranged to store electrical data. Memory devices typically include a number of memory cells that store individual bits of information. A bit may be represented by one or more voltages stored in a memory cell. For example, a single ended memory cell may store charges in a transistor, one charge level representing a “0” and the other representing a “1,” and in turn, current through the transistor is read to determine the value of the bit. A differential memory cell may store charges separately in two transistors. The difference between the currents through the transistors, when compared to a threshold, indicates the value of the bit. Many of these memory cells can be arranged in an array of rows and columns to store many bits of information.
In non-volatile applications, the charges stored in a transistor are stored at a floating gate of the transistor. In order to store and remove charges at the floating gate, high-voltage may be applied to the transistor. Typically, charge pumps generate the high-voltage and high-voltage (HV) switches control the high-voltage signals output to the memory array. Traditionally, a single HV switch is used to generate a single high/low signal of a function, such as the programming or erasing of memory cells within the array. Thus, an embedded memory application may include multiple HV switches that consume substantial area in a memory device in addition to the memory array.